Batch Aus Dateinamen nach bestimmten Zeichen kommende Zeichen als Variable speichern

@echo off &setlocal
set "folder=c:\data"  
set "filter=*.exe"  
for /f "delims=" %%a in ('powershell -Executionpolicy ByPass -Noprofile -Command "dir '%folder%' -filter '%filter%' | ?{!$_.PSIsContainer -and $_.Basename -cmatch 'A\d{2}'} | %%{$matches}"') do echo %%a  

@echo off & setlocal

set "Marker=A"  
set /a MarkerLen=1
set /a ExtractLen=MarkerLen+2

set "FileNames=TestlocalA19V.exe TestA21.EXE TestRemoteA19V.exe Test.RemoteA19V.Exe"  

for %%a in (%FileNames%) do (
  call :ProcessFileName "%%~a"  
)

exit /b 0



:ProcessFileName
  set "OutStr="  
  set "InStr=%~n1"  
  set /a Idx=0

  :Loop
    call set "SubStr=%%InStr:~%Idx%,%ExtractLen%%%"  
    call set "StartStr=%%SubStr:~0,%MarkerLen%%%"  

    if "%SubStr%" equ "" goto :LoopEnd  

    if "%StartStr%" equ "%Marker%" (  
      set "OutStr=%SubStr%"  
      goto :LoopEnd
    )

    set /a Idx+=1
    goto :Loop
  :LoopEnd

  call :ProcessFile "%~1" "%OutStr%"  
exit /b 0


:ProcessFile
  echo %~1 =^> %~2
exit /b 0

@echo off

set dateiname=TestlocalB19V.exe
REM TestlocalA19V.exe
echo %dateiname%

set variable=%dateiname:~-8,8%
REM A19V.exe
echo %variable%

set variable=%variable:~0,3%
REM A19
echo %variable%

if "%variable:~0,1%"=="A" echo Beginnt mit A  
if not "%variable:~0,1%"=="A" echo Beginnt nicht mit A  

for %%i in ("%cd%\*.exe") do set DATEI_NAME=%%~ni

for %%i in ("*.exe") do set DATEI_NAME=%%~ni

@echo off
pedate.exe ~biosversion /vo && call zavars.cmd && del zavars.cmd
set BiosVersion=%za-output%
echo Installiert ist die Bios-Version: %BiosVersion%